Magallana gigas (n = −33, tissue wet weight (w.w.) 14.31 ± 5.84 g), Ostrea edulis (n = −12, 7.15 ± 4.63 g w.w.) and Ruditapes philippinarum (n = −4, 2.46 ± 0.14 g w.w.) were collected from coastal locations in southern England and stored at −20 °C (Oaten et al., 2015). Defrosted soft tissues were removed from shells, placed in glass containers and re-frozen to −20 °C.
Contamination control measures were 100% cotton clothing, use of glassware and samples covered with aluminium foil. Whenever possible, work was performed in a clean air cabinet (Bassaire 03VB, BS EN ISO14644, class 5, with additional cover). Background contamination enumeration was deemed unnecessary as the microplastic enumeration that took place was of materials of known conspicuous appearance.